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New Morbid Terminology: Quicklime

Screenshot from Team Fortress 2 Video Game for Mann Co. Corpse Grad Quicklime, via Valve and Wiki for game

If you’re a fan of murder-mystery novels, you’ve probably run across quicklime before. It’s commonly cited in detective and mob stories as a method for quick and anonymous disposal of a body. Usually, the body is laid out on a tarp or placed in a burial, and then to prevent it from smelling and speed decay it is covered with quicklime. In movies and TV shows, the quicklime effectively destroys the body so that identification is prevented. In the video game Team Fortress 2, you’ll see numerous bags of Mann Co. Corpse Grade Quicklime throughout their factory. Despite the fact that you don’t get to use the bags of quicklime, it clearly displays what they think the material should be used for. In 1898, Oscar Wilde wrote a poetic description of the burial of Charles Woodridge lying dead in a coffin packed with quicklime:

Eats flesh and bone away

It eats the brittle bone by night

And the soft flesh by day

It eats the flesh and bones by turns

But it eats the heart away

-Oscar Wilde, The Ballard of Reading Gaol 1898

Quicklime is a chemical compound known as calcium oxide (CaO), and is made through the thermal decomposition of limestone or other materials containing calcium carbonate in a lime kiln. The material is heated at high temperatures, and the remains are quicklime. Quicklime is not a stable material, and will react with CO2 from the air causing it to convert into heat energy. Due to this reaction, it is used as a source of heat and light. Due to lime being an akaline product, contact with skin can cause reactions that range from mild irritation to full scale burning. It was commonly used to create spectacular theatrical bursts of light prior to the invention of electricity, and when used this way was known as limelight. Quicklime does have uses for burials. In the Red Cross Emergency Relief Items Catalogue, quicklime and lime are listed as a tool for aiding in proper disposal of human remains that cannot be afforded a deep burial. However, the goal of the product is not to destroy the body but rather to prevent putrefaction that create odor, and attracts flies and animals. Quicklime was often used over plague or cholera burials to prevent the spread of disease, thought during this period to be transferred through noxious bad air known as miasma (a morbid term for another day). Again, in practical usage quicklime is being used not to destroy but to prevent disease from spreading.

Lime is one of the major finds in many forensics cases dealing with clandestine burials due to this popular notion of its ability to remove the identity of the deceased and destroy the remains. A new study by Schotsmans et al. (2012) used pig corpses to test different types of lime to see how it changed the remains. The pigs were put into graves, covered with different types and amounts of lime, buried, and were left for six months. Two pigs were buried with lime as the control group. The pigs buried without lime were mostly skeletonized and highly decayed, the two pigs buried with hydrated lime were very well preserved and had little decay, and the two pigs buried with quicklime were fairly preserved with some decay within the body. In general, they discovered that the lime was highly effective in preventing decay and protecting the body, rather than destroying it.

Quicklime isn’t just for clandestine and diseased burials. In the Iron Age, quicklime burials were the normal form of disposal for a cultural group in the Balearic Islands in Spain. The burials are often found in caves and rock shelters along the coast. Each burial usually contains the bones of a single individual and a number of warped metal artifacts. The bones from these burials have variation in their appearance from light brown to pale white in coloration, and some of the bone shows warping and cracking typical of bone that has been heated at high temperatures. Traditionally, these burials have been interpreted as being inhumation within quicklime that caused the body to quickly decay and change in composition similar to a cremation burial due to the chemical effects of quicklime. However, Van Strydonck et al. (2013) argue that based on earlier experimental studies like Schotsmans et al. (2012), the warping and discoloration similar to cremation could not be caused by quicklime because it is more likely to preserve than destroy. They argue instead, that the remains were cremated and then placed in the quicklime. They posit that the bodies of this Iron Age group were cremated within their grave. The grave was probably filled with crushed limestone, which when heated during the cremation process were turned into a quicklime lining.

Quicklime is an interesting substance. It is popular for its mythological ability to remove identities from remains and destroy bones, but it also has a history of being used in to remove miasmas and was part of ritual processes such as the Iron Age burials. More likely if you see quicklime being used today, it is probably for a mundane purpose like making cement so don’t necessarily jump to conclusions. Now go forth and use this knowledge to tear apart your friends’ theories on disposing of a body!

In 1916 in Dublin City the English army burnt our town
Shelled the buildings shot our leaders the harp was buried beneath the crown

They shot McDermott and Pearse and Plunkett they shot McDonagh Ceannt and Clarke the brave
From bleak Kilmanham they took their bodies to Arbour hill to a quicklime grave
Last of all of the seven leaders they shot down James Connolly
The voice of labour the voice of justice gave his life that we might be free

Lime light is derived from Calcium Carbide (CaC2) which reacts strongly with water to produce acetylene gas (H2C2). This burns with an extremely bright light due to incandescent carbom particles in the flame from incomplete combustion. The “ash” is slaked lime, Ca(OH)2

The best know property of quicklime is not so much its reversion to limestone (by reaction with CO2) so much as its reaction with water (the so-called slaking of lime). That creates a great deal of heat in a short space of time. The classic lab demonstration is to drip a little water onto a biggish chunk of quicklime. It quickly soaks in, there’s often a deceptive lag before anything happens, then then the lump suddenly starts to swell, to develop fissures, cracks open and disintegrates releasing torrents of steam. Spectacular

Calcium oxide + water = calcium hydroxide + heat

Maybe the theory was a body placed in quicklime would cook and disintegrate, but conditions would have to be just right for that to happen, and it’s maybe not surprising that one ends up with a preserved body, especially as calcium hydroxide (slaked lime) is highly alkaline with antiseptic properties.

I got to thinking about slaked lime and bodies this morning, through being interested in the Shroud of Turin. Thus far I’ve been inclined to think the image is of medieval origin, consistent with the radiocarbon dating (1260-1390) and maybe produced by ‘branding’ linen from a heated bronze statue or similar. Might there be a chemical component too, one that produces heat in contact with water, or even a moist corpse? Suppose a body of a fallen crusader knight have been wrapped in linen and then encased in quicklime to preserve it on its journey back from the Holy Land? Might that have left an image on the linen that is what we now call the Turin Shroud, or maybe implanted the idea of how an image might be produced to order by thermochemical action?